Genetic variability for weed competitiveness and molecular characterization of introgression from Oryza glaberrima into rice (Oryza sativa L.)
2007
Santos, R.E.M., Philippines Univ. Los Banos, College, Laguna (Philippines)
Genetic variability was evaluated in a set of Oryza glaberrima accessions and 112 alien introgression lines (AILs) derived from the cross of O. sativa x O. glaberrima for traits related to weed competitive ability. Total biomass, above-ground biomass, leaf number, leaf length, culm length, root length, and seedling height were measured at three growth stages (7, 14, and 21 days after sowing). One of the O. glaberrima accessions, TOG5681 was found to be the best performing line both in monoculture and rice-weed mixtures. Two introgression lines, IR77384-17-3-19-3-B and IR77384-36-B-10-7-B were superior in performance in monoculture but showed inconsistencies in performance in rice-weed mixture. Weed competitive ability based on traits mentioned is best observe at growth stage 2 when there is a significantly different performance among genotypes in monoculture and rice-weed mixture. A set of 194 SSR [simple sequence repeat] markers was used to detect introgression from O. glaberrima in the 112 AILs. Parental survey revealed 64 percent polymorphism between the two parents. Chromosome segmental substitution lines (CSSL) and molecular map were constructed. Introgressed segments in the CSSLs ranged from zero to two in chromosome 2 and zero to seven in chromosome 6. Non-parental alleles were also detected in some of the AILs.
显示更多 [+] 显示较少 [-]